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A hospital needs 3,100 units of a medicine throughout the year. The purchasing cost varies with the size of the order. If the number of units of the medicine that the hospital orders is below 100 , the supplier charges $30 per unit; if it is between 100 and 499 , the price is $27 each; and if they order 500 units and above, it is $26 per unit. The holding cost per unit per year is $30, as the medicine must be kept in a special device to prevent spoilage. The ordering cost is $10. a. How many units of the medicine can hospital order each time to minimize their total cost? (Round your answer to a whole number.) b. What is the minimum annual total cost? (Round your answer to a whole number.) Answer is complete but not entirely correct. A hospital needs 3,100 units of a medicine throughout the year. The purchasing cost varies with the size of the order. If the number of units of the medicine that the hospital orders is below 100 , the supplier charges $30 per unit; if it is between 100 and 499 , the price is $27 each; and if they order 500 units and above, it is $26 per unit. The holding cost per unit per year is $30, as the medicine must be kept in a special device to prevent spoilage. The ordering cost is $10. a. How many units of the medicine can hospital order each time to minimize their total cost? (Round your answer to a whole number.) b. What is the minimum annual total cost? (Round your answer to a whole number.) Answer is complete but not entirely correct